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Springing the trap: A pH-responsive mesoporous silica nanoparticle with a calcium phosphate (CaP) pore-blocking coating was developed by enzyme-mediated surface mineralization under mild conditions. Upon exposure to cellular lysosomal pH, guest anticancer drug was released from the pore by dissolution of the CaP pore blocker (see picture; HAp=hydroxyapatite).
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Rim et al. (2011) studied this question.
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